Tik Tak Too - a tandem kayak-ish
August 23, 2014
The Tik Tak Too is a larger, 2-person version of the Tik
Tak Kayak. Same construction techniques, only with a 3rd sheet
of plywood and 12' sticks instead of 8'.
What follows is a picture essay of the prototype build, an explanation
of some of the techniques used, and some of the problems encountered.
The first problem was my selection of plywood. I used 1/4"
ACX which is a fine boat building material, but it is heavier than
5mm Luaun. Light boats get used more.
First step: Stack your plywood. I like to make my mistakes all
at once, so I do my cutting all at once. I use the rubber mallet
to tap the edges into alignment, then clamp everything together.
4x8 sheets of ply are too big for me to wrestle onto my tablesaw
by myself, so I use a circular saw with a rip fence (or you could
save $30 and just draw a line.) The fence is also handy for ripping
chines, a process not shown here. Cut the ply into 3 planks: 32"
for the bottom and top*, 10: for the sides, and the remainder is
used for butt straps and whatever - there is a fair bit of waste
in this plan.
*32" ended up being a bit difficult to move around. The HULLS
program says a 32" wide Tik Tak Too will displace 4" at
540lbs, ~500 at 30" wide, and around 450 at 28" wide.
A wider boat is more stable, but a thinner boat will be easier to
The butt straps I used were 3" wide, 12x the thickness of
the ply. Next time, I'll make 'em 4" wide, the
recommended 16x the thickness.
The butt straps have to fit inside the chines when the boat is
assembled, so even though the side planks are 10" wide, the
butt strap is only 8 1/2" (10" minus the width of each
chine.) The butt straps for the bottom are even trickier - you need
to take the thickness of the sides into account (make them 2"
shorter than the width of the hull.)
I used a steady hand and a sabersaw to cut one of the 32x96 planks
and one of the 10x96 planks into planks 48" wide. Even being
careful, the cut was wiggly. I ended up using the wiggly ends as
the outer edge, butting the factory edges together for the joint.
To get the curves for the ends, I clamped one of the chines to
the edge of one of the 8' side planks. Rather than have a smooth
curve over the whole length, I wanted the bottom (and top) to be
flat. The curve meets the top and bottom of the plank 42" from
Again, I wanted to make all my cuts at once. I stacked all the
pieces, face to face to get mirror images. This is tricky and fraught
with danger - mess up and you have 4 errors instead but . . . it
Since the boards were stacked, I went ahead and pre-drilled pilot
holes for the screws I'll be using to attach the chine logs.
The parts of the curve that are cut off become skegs, should you
choose to use them.
I butted everything together and glued and screwed it down. Make
sure to use a glue-proof barrier under your planks (I used Saran
Centerlines will be very important.
I cut my chine logs from a 12' 2x6, so they are barely long enough
to use. Once glued and screwed into place, trim off the excess.
The first chine is easy, the second one requires a little fitting.
Glue/screw the middle section into place, bend the chine into place
make some marks.
Flip the plank over and use your trusty saw to connect your marks.
Wow It worked! By the way, I'm using TiteBond III for the glue
on these tight fitting surfaces. Note: Only 2 of the ends came out
this tight, but it doesn't matter as I used PL Premium - and expanding
polyurethane construction adhesive - to attach the top and bottom.
That glue fills any little gaps or mistakes.
You want the sides to be exact mirror images to reduce any twist
to the boat. Clamp them face to face, mark one edge Top and one
end Forward so you can keep things straight during assembly.
Plane and sand the edges smooth.
Make sure you mark the centerline - it's important to get the pieces
lined up during assembly.
I use clamps to hold the sides vertical as I attach the bottom.
I dry fit everything together, start the screws (with fender washers
to distribute the force,) then prop up one edge. Run a generous
glue line along the chine, removing the braces when you get to them.
Line everything up, start in the middle, and screw it down. Repeat
on the other side.
Chines and stems, let it cure (4 hours, minimum for PL Premium)
Remove the screws and fill the holes with toothpicks dipped in
glue. I've become so cheap I cut the toothpicks in half.
Cut the hatch before you attach the top. I made the hatch 72"
long by 24" wide. I like the round ends - they look nice.
The wood cut from the hatch is used to double the thickness of
the bottom - the butt strap just buggers things up, so I cut it
out and glued/screwed the pieces into place.
Do yourself a favor and paint the insides before attaching the
top deck. Those ends are hard to paint once everything is together.
Make sure to tape off any glue surfaces: Paint sticks to glue, glue
does not stick to paint.
The midpoint marks make it easy to line up the top deck when gluing/screwing
it into place. You might need to push/pull the side into alignment,
do your best to get the edges to mate up smoothly.
I found it necessary to clamp the ends shut - the screws were providing
enough force. I made sure I used an excess of glue to fill any gaps
I decided to go with a couple 1x1s for the coaming. The gap is
to let any accumulated water out.
2 coats of primer, 2 coats of porch paint. I drilled holes for
the painter through the stems at both ends of the boat. I decided
not to use skegs, so the boat is truly symmetrical and could be
paddled in either direction.
Mostly because of the ACX plywood, this prototype came out to ~71
lbs, a little heavy. Just over 2 lbs of that is paint.
She floats in 3/4" of water.
Using a throw PFD as a seat, I tried sitting just aft of center
first. It worked OK, but sitting about 8' from the bow worked fine,
too. A 200lbs paddler doesn't seem to be able to get the transom
to touch the water.
It paddled just fine - smoothly and easily. Even without skegs,
it wasn't too squirrely. There's tons of space and it is very, very
stable. It'll be a fine design for one or two people on calm, flat
You can see the top deck developed a little bit of a scoop to it.
That can be solved a couple of ways - I just chose to ignore it.
The biggest concern is the weight. 70+ lbs isn't bad, but it's
not really easy to move around, either. I think going to a 30"
wide hull would make moving it on dry land easier, too.